Trailer for transporting freight containers and method of use

ABSTRACT

A trailer for transporting a freight container is comprised of a frame having a front frame section which is adapted to be coupled to a suitable road vehicle. A pair of displaceable horizontal side beams are secured to the front frame section and are provided with a hingeable rear gate formed by a pair of hinge arms. Each of the side beams has a suspension assembly to support a tandem wheel arrangement. Retractable vertical lifting piston cylinders are secured to a portion of the front frame and to the pair of hinge arms and are actuable to lift the pair of horizontal side beams and its wheels above a ground surface. Laterally extendable piston cylinders are also secured to the front frame and the hinge arms to displace the horizontal side beams outwardly and inwardly with respect to one another when lifted off the ground surface. Container lifting posts are secured to opposed ends of the front frame section and the hinge arms for removable connection to a container positioned between the side beams to lift and lower the container therebetween. Container connectors are secured to each of the side beams for securing a container thereto for transportation.

TECHNICAL FIELD

The present invention relates to a trailer for transporting a freightcontainer and its method of use. Preferably, but not exclusively, thecontainer is an ISO certified container.

BACKGROUND ART

Container handling transport vehicles of various types are known fortransporting different types of freight containers on existing publicroads. However, these transport vehicles and containers have to abide togovernment regulations when traveling on such public roads. Accordingly,containers are manufactured with strict design regulations as to size.ISO certified containers are also fabricated with specific attachmentswhereby to be handled and secured during transport, whether by land, seaor air. Handling equipment is also designed to engage these attachmentsfor secure handling and transportation. The trailer design of thepresent invention is particularly adapted to handle such ISO certifiedcontainers which can be rested directly on a ground surface anddifficult to access location. Accordingly, there is no requirement toprovide elevated frames to support the container elevated for transferonto conventional trailers such as described for example in U.S. Pat.Nos. 5,417,540, 6,155,770, 6,532,398 and others.

Transporters for picking up containers lying on ground and transferringthem on a transport vehicle support frame are also known. A most commontype are those open top end containers in which refuse from buildingsites are deposited and later picked up by pulling the container on apivoted support frame by a winch and cable, the container is thenpositively engaged for transport to a refuse disposal site. Othervehicles are also known to handle specific size shipping containersresting on ground, as described in U.S. Pat. No. 6,910,844. Trailertransporters are also known to handle shipping containers resting onground. U.S. Pat. No. 4,120,413 describes a trailer having adjustableside rails and lift cylinders to load a container onto the side railsfor transportation. As well, U.S. Application 2004/0223835 published onNov. 11, 2004, describes a trailer having a U-shaped frame and liftingmembers to lift a container from a ground surface for transportation.The U-shaped frame is provided with a rear gate. The present inventionis concerned with a trailer container transporter of the general type asdescribed in these later two patents referred to.

Briefly, summarizing some of the disadvantages of prior art containerroad transporters, they are expensive to fabricate, bulky, timeconsuming to load and unload, require at least two operators, some needhoist or ground support equipment and some cannot operate on rough roadconditions or maneuver to pick up containers in restricted spaces andcontainers resting directly on the ground without supports. Some of thetrailer type transporters also do not provide adequate shock damping andcan cause damage to the contents of the container during transport onrough roads.

SUMMARY OF THE INVENTION

It is a feature of the present invention to provide a trailer fortransporting a container which is preferably, but not exclusively, ISOcertified and capable of transporting the container on public roads by apick-up truck or other small tractor vehicles by means of a fifth wheelattachment.

Another feature of the present invention is to provide a trailer fortransporting a container and wherein the trailer has a pair ofhorizontal side beams that are displaceably adjustable in a horizontalplane to permit handling of containers of different sizes and whichfacilitates the engagement of the trailer with the container.

Another feature of the present invention is to provide a trailer fortransporting a container and which requires a single person to operateand to load and unload a container therefrom.

Another feature of the present invention is to provide a trailer fortransporting a container and wherein the trailer is provided withconnectors to secure ISO certified containers of different sizesthereto.

Another feature if the present invention is to provide a trailer fortransporting a container and which is comprised of displaceablehorizontal side beams, each side beam being provided with a wheelsuspension to permit the travel of the trailer with a container onpublic road surfaces or rough road surfaces while providing adequateshock absorption.

Another feature of the present invention is to provide a trailer fortransporting a container and wherein the trailer can be engaged with acontainer disposed in a restricted space.

Another feature of the present invention is to provide a method oftransporting a container from a rest position on a ground surface andwherein the container can be loaded on the trailer by a single personand in a substantially horizontal manner.

According to the above features, from a broad aspect, the presentinvention provides a trailer for transporting a freight container. Thetrailer is comprised of a frame having a front frame section adapted tobe coupled to a road vehicle. The frame further has a pair ofdisplaceable horizontal side beams. A hingeable rear gate is formed by apair of hinged arms which are hingedly secured to a rear end of arespective one of the horizontal side beams. Each of the horizontal sidebeams has one or more wheels independently secured thereto by suspensionmeans. Retractable vertical lifting means is secured to a portion of thefront frame and the pair of hinged arms and actuable to lift the pair ofhorizontal side beams with its one or more wheels above a groundsurface. Laterally extendable means is secured to the front frame andthe hinge arms to displace the horizontal side beams outwardly andinwardly with respect to one another when lifted off the ground surfaceby the retractable vertical lifting means. Container lifting andlowering means is also secured to the front frame section and the hingearms for removal connection to a container positioned between the sidebeams to lift and lower the container therebetween in a substantiallyhorizontal plane. Container connecting means is secured to each of theside beams for securing the container thereto for transportation.

According to a further broad aspect of the present invention, there isprovided a method of transporting a container from a rest position on aground surface. The method comprises the steps of: i) providing atrailer having a frontal frame section, a pair of displaceable sidebeams, and a hingeable rear gate formed by a pair of hinge arms, each ofthe hinge arms being hingedly secured to a rear end of a respective oneof the side beams, and wheels secured by suspension means to each of theside beams; ii) lifting the trailer and wheels off a ground surface byoperating a retractable vertical lifting means secured to the frontframe and the pair of hinge arms; iii) extending the side beamsoutwardly by operating laterally extendable means secured to the frontframe and the hinge arms; iv) lowering the trailer back on the groundsurface by operating the retractable-vertical lifting means; v) openingthe rear gate to create a rear entry opening; vi) positioning thetrailer about the container from the rear entry opening; vii) closingthe rear gate; viii) engaging container lifting and lowering means withthe container; ix) lifting the container above the side beams in asubstantially horizontal manner; x) repeat step (ii); xi) retract theside beams inwardly by operating the laterally extendable means to alignthe side beams with corner connections of the container; xii) repeatstep (iv); xiii) lower the container in said substantially horizontalmanner onto connecting means secured to the side beams and engage theconnecting means with the corner connections of the container.

According to a further broad aspect of the present invention there isprovided a wheel supporting suspension for securing a wheel to opposedsides of a trailer frame. The suspension comprises a pivoted wheelsupport arm secured at a forward pivot end to a pivot pin retained in aframe attachment member for pivotal connection of the pivoted wheelsupport arm to the frame. A wheel axle assembly is secured at a rearfree end of the pivot arm and adapted to connect a wheel thereto. Ashock absorber connecting bracket is secured to the forward pivot end ofthe pivotal wheel support arm and has a shock absorber connecting memberextending above the pivot pin. The shock absorber connecting member ispivotally displaceable in facial alignment with a stationary shockabsorber connector secured to the frame. A shock absorber is retainedcaptive between the shock absorber connecting member and the stationaryshock absorber connector and compressible therebetween by the shockabsorber connecting member being displaced towards the stationary shockabsorber connector by upward movement of the pivot wheel support arm toabsorb vertical displacement loads transmitted to the pivotal wheelsupport arm by the wheel connected thereto.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the present invention will now be describedwith reference to the accompanying drawings in which:

FIG. 1 is a side view showing the trailer of the present inventionsecured to a fifth wheel connection of a pick-up truck and wherein acontainer has been loaded onto the trailer;

FIG. 2 is a perspective view of the trailer showing some of thecomponent parts thereof;

FIG. 3 is a top view of FIG. 2;

FIG. 4 is a rear view of FIG. 2;

FIG. 5 is an exploded view showing the construction of the retractablevertical lifting mechanism to lift the pair of horizontal side beams andits wheels above a ground surface;

FIG. 6 is a perspective view of the coupling connector connected to thelifting cylinder of the container lifting and lowering posts;

FIG. 7 is a perspective view showing the connection of a containercorner locking device for engaging ISO certified containers;

FIG. 8 is a fragmented perspective view of the transverse extendableconnecting mechanism as secured to one of the rear gate hinge arms;

FIG. 9 is a further perspective view of the trailer of the presentinvention as seen from a different angle;

FIG. 10 is a further perspective view of the transverse extendableconnecting mechanism as secured to the front frame section of thetrailer but with some portions thereof having been removed to show thecylinder connection;

FIG. 11 is an enlarged fragmented view showing the construction of thecontainer alignment pads secured on the inner face of the horizontalside beam;

FIG. 12 is a perspective view of a pair of wheel supporting suspensionconstructed in accordance with the present invention for securement to atrailer frame;

FIG. 13 shows two of the wheel supporting suspensions secured to atrailer side frame with one of the suspensions having the wheel removedtherefrom for the purpose of illustration;

FIG. 14 is a top view showing two wheel supporting suspensions securedto the trailer side frame on an outer side of the side frame;

FIG. 15 is a side view showing the operation of the independentsuspensions when encountering obstacles on a road;

FIGS. 16A to 16C are side views showing the operation of the wheelsupporting suspension from an unloaded position to a fully loadedposition; and

FIGS. 17A to 17K are side views showing the method of use of the trailerof the present invention for engaging a container resting on a groundsurface.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to the drawings and more particularly to FIGS. 1 to 4,there is shown generally at 10 the container transport trailer of thepresent invention for transporting a freight container 11 andpreferably, but not exclusively, ISO certified containers. The trailer10 has a front frame section 12 provided with a towing frame structure13 for removable attachment to a hitch 14, herein a fifth wheel hitch,secured in the box 15 of a pick-up truck 16. It is also conceivable thatinstead of a pick-up truck that a tractor or a motorized cab may beconstructed particularly suited to handle the trailer 10 of the presentinvention with the trailer 10 secured to a pivotal connection (notshown) in the rear of the cab by a different type of towing framestructure, for attachment to a coupling plate of a tractor or a pintlehook of a truck or trailer.

Details of the trailer will now be described with further reference toFIGS. 2 to 4. As herein shown, the trailer 10 has a front frame section12, as above-described, and to which is secured a pair of displaceablehorizontal side beams 17 and 17′ which are displaceable in substantiallyparallel planar relationship to one another in an outward and inwarddirection, as will later be described. A hingeable rear gate 18 isformed by a pair of hinge arms 19 and 19′. Each hinge arm is hingedlysecured to a respective one of the horizontal side beams 17 and 17′ at arear end 20 and 20′ of the side beams 17 and 17′, respectively. Thehinge arms 19 and 19′, when in their closed position, as illustrated inFIGS. 2 and 3, are interlocked at their free ends by a locking mechanism90 which is actuated by a locking arm 91 as better illustrated in FIG.4. Details of this mechanism are not illustrated herein as any suitabletype of locking mechanism is conceived to interlock the hinge arms 19and 19′ in their closed position.

Each of the horizontal side beams 17 and 17′ are provided one or more,herein two, wheel supporting suspension assemblies 21 and 21′respectively, and independently displaceable to absorb shocks. Thissuspension 21 and 21′ will be described in more detail later.

Retractable vertical lifting means in the form of vertically supportedtelescopic lifting legs 23 are secured to a portion of the front frame12, herein adjacent opposed ends thereof, inside the horizontal side arm17. These telescopic lifting legs 23 are also secured to each of thehinge arms 19 and 19′ adjacent their inner end portions thereof. Whenthese telescopic vertical lifting legs are extended they lift thehorizontal side beams 17 and 17′, as well as the wheels 22, off theground surface. This is necessary in order to actuate laterallyextendable means, namely pistons 50, which forms part of a transverseextendable connecting mechanisms 24 secured to each of the hinge arms 19and 19′ and to opposed sides of the front frame section 12 whereby todisplace the horizontal side beams 17 outwardly and inwardly withrespect to one another. The side beams may be displaced independently orin unison by operating the hydraulic controls 36.

The trailer 10 is further provided with container lifting and loweringposts, herein four such posts 25, secured in a respective one of fourcorner areas of the trailer frame. These container lifting posts 25permit removable connection to a container 11 positioned between theside beams 17 and 17′ to lift and lower the container therebetween, in asubstantially horizontal plane, to permit engagement of the containeronto the horizontal side beams 17 and 17′ as will be described later.Container connecting means in the form of container locking devices 26are also secured on a top surface 27 of the horizontal side beams 17.Only four such container locking devices 26 are herein shown but theside beams may be fitted with attachments to removably secure additionalones of the locking devices for handling containers of differentlengths. These container locking devices 26 are also adapted to secureto the attachments provided in the corners of ISO certified containersor other such containers and they are well known in the art. The sidebeams 17 and 17′ are capable of each supporting a load of 4800 lbs. fora total handling capacity of 19,200 lbs. and a total load of 22,700 lbs.on the suspension of four wheels for the “pick-up truck” version hereinillustrated.

Referring to FIG. 5, there is shown in exploded view, the bottom portionof the telescopic vertical support leg assembly 23 as identified in thecircled portion A of FIG. 2. The vertically supported telescopic legassembly 23 comprises a steel tube 30 in which there is slidingly andtelescopically received a steel post 31 constituting the leg. A hingedfoot plate 32 is secured to the bottom end of the post 31 to engage theground surface. The post 31 is slidingly received within the tube 30 anddisplaceable by a piston rod end connection 33 secured to the free endof piston rod 34 of piston cylinder 35. All piston cylinders 35 may beoperated in unison by the hydraulic controls 36 conveniently located atthe front end of the trailer 10 next to the hydraulic unit 37.Alternatively, they may be operated individually if need be to lift thecontainer 11 substantially horizontally not to displace the freightcontained therein.

FIG. 7 illustrates the construction of the container locking device 26as shown in the circled portion B in FIG. 2 and this locking device ispositioned to be received within the corner connectors of the container,as is well known in the art. Accordingly, their construction andoperation will not be described herein, sufficient only to say that, asshown in FIG. 3, these are located at a precise location on the topsurface 27 of the horizontal side beams 17 and 17′ to engage with thelocking connectors in the four bottom corners of the ISO certifiedcontainer.

FIG. 6 is a perspective view of the circle portion C of FIG. 2 butpartly fragmented whereby only the mechanism mounted in the lifting post25 is shown herein. As herein shown, a piston lifting cylinder 38 issecured within each of the posts 25 and it has a piston rod endconnection 39 secured to a coupling connector 40 which has a connectingflange 42 which is vertically displaced along a vertical slot opening 41in the lower section of the post 25, as shown in FIG. 2. The connectingflange 42 which slides along the slot 40 and extends outwardly thereof.The connecting ear 42 has an attachment hole 43 to secure a chain 44thereto. The chain 44 has a hook 45 at its end, as shown in FIG. 2, towhich a container coupling connector 46 is secured to engage theconnectors 47 provided in the four corners of the container 11, as shownin FIG. 1. These coupling connectors 46 are engaged while the container11 is resting on the ground surface. By actuating these piston liftingcylinders 38 by the controls 36 the container is lifted off the groundin a substantially horizontal plane to safeguard its content. After thecontainer is re-deposited onto the ground or ground supports, aftertransport to its destination, the connectors are disengaged. If thecontainer is not lying horizontally, the length of the chains can beadjusted to compensate for the tilt of the container if all of thelifting cylinders are to be operated simultaneously.

FIG. 8 is an enlarged view of the circle portion D of FIG. 2 andillustrates, in part, the construction of the transverse extendableconnecting mechanism 24. One of these extendable connecting mechanisms24 is secured to opposed sides of the front frame section 12 and to eachof the hingeable rear gates. The detail D shows the mechanism secured toone of the hingeable rear gates, herein gate 19. FIG. 8 will bedescribed with further reference to FIG. 10 which shows part of theextendable connection 24 secured to the front frame section but withparts thereof having been removed to illustrate the entire construction.As herein shown, the extendable connecting mechanism has a hydraulicpiston cylinder 50 having a piston rod end connection 51 secured to thehorizontal side beams 17 and 17′ and by actuating the cylinder 50, byuse of the manual controls 36, the horizontal side arms 17 and 17′ canbe displaced outwardly and inwardly with respect to one another. To doso the side beam needs to be coupled at opposed ends to the front framesection 12 and to associated one of the hinge arms 19 and 19′ by asliding coupling assembly 52 as shown in FIG. 8.

The sliding coupling assembly 52 is constituted by a slide plate 53which is secured to a hinge flange 54 attached to a hinge connection 55at the rear end 20 and 20′ of the side beams 17 and 17′, respectively.The slide plate 53 is displaceably retained captive between guide wheels56, one of which is not shown in FIG. 8 for ease of illustration, andwhich are secured to the hinge arms, herein hinge arm 19, to permitsliding displacement of the slide plate 53 therebetween and along astraight longitudinal axis of the hinge arm. This slide plate 53 isshaped to extend over the cylinder 50, which is not shown in FIG. 8, butlocated therebehind. Accordingly, the slide plate 53 also provides acover for the cylinder 50 to protect it from foreign matter. These guidewheels 56 are disposed for frictional rotational engagement with opposedparallel edge portions 53′ of the slide plate 53.

As shown in FIGS. 9 and 11, each of the side beams 17 and 17′ areprovided with container alignment pads 58 on the inner surface 17′″.FIG. 11 is an enlarged view of the circle portion E shown in FIG. 9which illustrates the shape and location of the pads 58. These containeralignment pads 58 protect the inner side surface 17′″ of the horizontalside arms 17 and 17′ while the trailer is backed-up about the container11. They also provide guides when the trailer is backed into and aboutthe container from the rear open gate, as will be described later. Also,and as shown in FIGS. 3 and 5, one or more bumpers 59 are secured to theinner side wall 59′ of the front frame section 12 to provide an abutmentagainst the container forward end when the trailer is backed in aroundthe container.

With reference now to FIGS. 12 to 16C, there will be described theconstruction and operation of the wheel supporting suspension assembly21. There are two suspension wheel assemblies 21 shown in FIG. 2 andshown in engagement with the side beam 17 of the trailer on an outboardside thereof. As shown in FIG. 13 there are two such wheel supportingsuspension assemblies secured to each of the opposed side beams 17 and17′ and these suspensions operate individually. Each suspension assemblyis comprised of a pivoted wheel support arm 60 secured at a forwardpivot end to a pivot pin 61 (see FIG. 13) retained in a flame attachmentmember 62 for pivotal connection of the pivoted wheel support arm to theside beam 17 of the trailer frame.

A wheel axle assembly 63 is secured at a rear free end of the pivot arm60 and adapted to connect to a wheel 22 as previously described andillustrated in FIG. 2, for example. A shock absorber connecting bracket64 is secured to the forward pivot end of the pivotal wheel support arm60 and has a shock absorber connecting member 65 extending above thepivot pin 61 and spaced therefrom. The shock absorber connecting member65 is in the form of a flat seating plate secured to a support frame 66which forms part of the shock absorber connecting bracket 64. Aconnecting fastener in the form of a bolt 67 secures a compressibleshock absorber 68 in facial contact therewith and in a manner well knownin the art.

As shown in FIG. 13, when the wheel supporting suspension assembly 21 issecured to the side beam 17, the shock absorber seating plate 65 isdisposed in facial spaced relationship with respect to a stationaryshock absorber connector, herein a flat seating wall 69 formed at thefront end of a recessed wall portion 70 formed in the outboard portionof the side beams. There are two such recessed wall portions which arespaced-apart. The shock absorber pad 68 is retained captive between theshock absorber connecting plate 65 and the stationary vertical seatingplate 66 and compressible therebetween by the shock absorber connectingmember, herein the plate 65, being displaced towards the stationaryshock absorber plate 66 by the load imposed by the trailer frame and anyadditional load supported thereon which causes pivotal upward movementof the wheel support arm to absorb vertical displacement loadstransmitted to the arm by the wheel connected thereto and resting on theground surface.

As shown in FIGS. 12 and 13, the pivotal wheel support arm 60 is alsoprovided with a lateral displacement stabilizing vertical extensionplate 71 immovably secured to the pivotal wheel support arm 60. Theextension plate is provided with a vertical flat friction surface 71′which is displaceable against a flat vertical arresting surface, hereinthe vertical wall 70′ of the recess well portion 70 of the side beam onan outboard side of the side beam. This plate prevents lateraldisplacement of the support arm. As well, to add further lateralstability there is provided a bushing 72 of shock absorbing materialimmovably retained in the frame attachment member 62 as better seen inFIG. 15 and disposed about the pivot pin. This stabilizes the pivot pinjoint and absorbs forces that may be transmitted to the pivot pin. It ispointed out that the vertical flat friction surface 71′ of the verticalextension plate 71 is provided by an ultra-high molecular weightpolyurethane plate which is secured to a surface of the verticalextension plate by a fastener, such as fasteners 71″ shown in FIG. 12.

The wheel supporting suspensions 21 are secured to an underface of theside beam 17 by bolt fasteners or welding of the frame attachment member62, herein a connector plate 62′ to the undersurface of the side beamforwardly of the recessed wall portions or cavities 70.

The top view of FIG. 14 illustrates the position of the wheels 22 withrespect to the suspension assembly 21. FIG. 16A shows the suspensionassemblies 21 when secured to the trailer side beams 17 without acontainer connected to the trailer. The weight of the trailer isapproximately 1250 lbs. FIG. 16B illustrates the suspension in partialcompression when the trailer is loaded with a load of approximately22,700 lbs. As herein shown, the shock absorbers are compressed. FIG.16C shows the shock absorbers in maximum compression.

It is pointed out that this suspension assembly 21 was designed to beable to take a total load of 22,700 lbs. without a thru axle extendingacross the frame as between two wheels, as is conventional with tractortrailers. This suspension was designed whereby each side of a trailer isindependent from the other side. The smoothness of the ride is assuredby the independent suspension and shock absorbers. As shown in FIG. 15,while one wheel is pushed up in the direction of arrow 76 by a bump 75,thus creating a sudden load increase, the other wheel, herein wheel 22′,will remain independent. When the pivotal arm 60 is at the end of itstravel, the shock absorber 78 will be squeezed to absorb the energy.Both shock absorbers work independently.

As shown in FIG. 13, the spindle 63″ of the wheel axle assembly 63provides the link between the bearing (not shown) and the drum 63′″. Itis attached to the axle 63′ and it is a non-moving part of the wheelend. The drum 63′″ is the link between the wheel 22 and the spindle. Thewheel 22 is attached to the drum and the drum rotates on the spindlebearing (not shown). Electric brakes (not shown) are located inside thedrum and help the pick-up truck and trailer to brake faster and safer.

Referring again to FIG. 8, a manual locking device 80 is providedadjacent opposed ends of the side beams 17 and 17′, only one being shownherein, to lock the side beams with respect to the front frame section12 when displaced to an outward extended position and to also lock thehinge arms 19 and 19′ in an open position, substantially in alignmentwith the side beams when the side beams are in their outward position.Any convenient manual locking device may be provided to effect thisinterlocking and, as herein shown in FIG. 8, a lock pin 81 isdisplaceably retained in a bracket 82 secured to the lifting post 25whereby to engage with a further bracket 83 extending from the wheelsupporting top plate 84 of the guide wheels 56. The bracket 83 is alsoprovided with a hole 85 to receive the locking bolt 81 in lockingengagement therewith.

Having described the construction of the container transport trailer 10of the present invention, there will now be described its method of use.

With reference now to FIGS. 17A to 17K there is now described the methodof engaging the trailer 10 to the freight container 11. Firstly, asshown in FIG. 17A, the pick-up truck 16 positions the trailer 10 nearthe container 11 and in straight alignment therewith and far enough toprovide sufficient space to open the rear gate 18. The operator thenstarts the hydraulic unit 37 and, using the hydraulic controls 36,causes the telescopic lifting legs 23 to be extended, as shown in FIG.17B, and sufficiently to lift the trailer and its support wheels 22 offthe ground surface 93. The four corners of the horizontal side arms 17is manually unlocked from the locking mechanisms 80 and again using thehydraulic controls 36, the pistons 50 are actuated whereby to displacethe opposed side beams 17 and 17′ outwardly to enlarge the spacetherebetween sufficient to permit the trailer to be safely backed uparound the container without damage to the trailer or the container. Thehinge arms 19 and 19′ of the rear gate are then locked in their openposition by the locking mechanism 80. The telescopic lifting legs 23 arethen lifted by the hydraulic controls 36 so that the trailer wheels areagain resting on the ground. The trailer is then ready to be backed upabout the container, as shown in FIG. 17C.

The operator of the pick-up truck 16 slowly backs the trailer about thecontainer 11 until the container hits the bumper 59 secured to the innerface of the front frame section 12. The operator then engages theparking brake on the pick-up truck and is now in a position to load thecontainer, as shown in FIG. 17E. However, before doing so, the hingeablerear gate 18 is closed and the hinge arms 19 and 19′ are lockedtogether. With the use of the hydraulic controls 36, the couplingconnectors 40 in the container lifting post 25 are lowered and theconnector 46 is positioned adjacent a corner of the container where theconnectors 46 are engaged within the corner connectors 47 of thecontainer 11. This attachment to the container is done manually by theoperator in the four corners of the container. The lifting cylinders 38in the container lifting posts are then actuated in unison orindependently to adjust the level of the container. The cylinders 38withdraw the coupling connector 40 upwardly whereby to lift thecontainer above the horizontal side arm 17, as shown is FIG. 17G in asubstantially horizontal manner. This position is also shown in FIG.17H. FIG. 17F shows a container lying on the ground prior to beinglifted. As shown is FIG. 17G, the container lies above the containerlocking devices 26 on the top surface of the horizontal side beams 17and 17′. At this position the lifting cylinders are at their end oftravel and the container is lifted substantially horizontally not todisturb its cargo or freight.

With the container positioned as shown in FIG. 17G the horizontal sidebeams 17 and 17′ and their wheels 22 now need to be lifted off theground surface 93 by the actuation of the telescopic lifting legs 23 andthis is illustrated in FIG. 17I. The wheels 22 should not touch theground surface when lifted to that position. The pistons 50 are thenactuated by the hydraulic controls to retract the horizontal side arms17 and 17′ to their original closed positions where the containerlocking devices 26 should be aligned with the lower corner connectors 47of the container 11. The telescopic lifting legs 23 are then retractedso that the wheels are again in engagement with the ground surface 93.Thereafter, the coupling connectors 40 in the container lifting post 25are lowered by the use of the hydraulic controls 36 to position thecorner connectors in the locking devices 26 where they are then engagedwith the horizontal side arm 17 of the frame of the trailer 10. Afterthe container locking devices are engaged the operator inspects thetrailer to ensure that all locking devices are secured in position. Thetrailer is now ready to transport the container to a further locationwhere the container is unloaded by going through the same process but inreverse mode.

It is within the ambit of the present invention to cover any obviousmodifications of the preferred embodiment described herein, providedsuch modifications fall within the scope of the appended claims.

1. A trailer for transporting a freight container, said trailercomprising a frame having a front frame section adapted to be coupled toa road vehicle, said frame further having a pair of displaceablehorizontal side beams, a hingeable rear gate formed by a pair of hingearms, each said hinge arm being hingedly secured to a rear end of arespective one of said horizontal side beams at a rear end of said sidebeams, each of said horizontal side beams having a wheel supportingsuspension secured thereto, and one or more wheels secured to saidsuspension, retractable vertical lifting means secured to a portion ofsaid front frame and said pair of hinge arms and being actuable to liftsaid pair of horizontal side beams and said one or more wheels above aground surface, laterally extendable means secured to said front framesection and said hinge arms to displace said horizontal side beamsoutwardly and inwardly with respect to one another when lifted off theground surface by said retractable vertical lifting means, containerlifting and lowering means secured to said front frame section and saidhinge arms for removable connection to a container positioned betweensaid side beams to lift and lower the container therebetween, andcontainer connecting means secured to each said side beams for securingthe container thereto for transportation.
 2. A trailer as claimed inclaim 1, wherein said retractable lifting means are vertically supportedtelescopic legs secured on opposed sides of said front frame, and toeach of said hinge arms, and a hydraulic piston secured to each saidtelescopic legs to cause extension and retraction thereof.
 3. A traileras claimed in claim 1, wherein each side beam of said pair of horizontalside beams is provided at a front and rear end thereof with a transverseextendable connecting linkage, said extendable connecting linkage atsaid front end being displaceably secured to said front frame sectionand at said rear end being displaceably secured to a respective one ofsaid pair of hinge arms, each said extendable connecting linkage havinga hydraulic piston constituting said laterally extendable means.
 4. Atrailer as claimed in claim 3, wherein each said transverse extendablelinkage is a sliding coupling assembly.
 5. A trailer as claimed in claim4, wherein each said sliding coupling assembly at said rear end of saidside beams is constituted by a slide plate secured to a hinge flangeattached to a hinge connection at said rear end of said side beams, saidslide plate being displaceably retained captive between guide memberssecured to said hinge arm for sliding displacement along a straightlongitudinal axis of said hinge arm.
 6. A trailer as claimed in claim 5,wherein said guide members are spaced apart guide wheels in frictionalrotational engagement with opposed parallel edge portions of said slideplate.
 7. A trailer as claimed in claim 1, wherein said containerconnecting means is a container corner locking device secured adjacentopposed ends of a top surface of each said side beams for lockingengagement with lower corner engaging formations of ISO certifiedcontainers.
 8. A trailer as claimed in claim 1, wherein each of saidside beams are provided with container alignment pads on an inner sidesurface thereof.
 9. A trailer as claimed in claim 1, wherein saidcontainer lifting and lowering means are constituted by four verticalposts, each said post being secured in a respective one of four cornerareas of said frame, a lifting piston mounted in said posts, saidlifting piston having a piston rod end secured to a coupling connectorfor displacement of said coupling connector along a vertical slotopening of said post, said coupling connector being adapted forremovable attachment to a container.
 10. A trailer as claimed in claim1, wherein there is further provided a container arresting bumpersecured to an inner face of said front frame.
 11. A trailer as claimedin claim 1, wherein said suspension means comprises a pivotal wheelsupport arm secured at a forward pivot end to a pivot pin retained in aframe attachment member for pivotal connection of said pivotal wheelsupport arm to said frame, a wheel axle assembly secured at a rear freeend of said pivotal wheel arm and adapted to connect a wheel thereto, ashock absorber connecting bracket secured to said forward pivot end ofsaid pivotal wheel support arm and having a shock absorber connectingmember extending above said pivot pin, said shock absorber connectingmember being pivotally displaceable in facial alignment with astationary shock absorber connector secured to said frame, a shockabsorber retained captive between said shock absorber connecting memberand said stationary shock absorber connector and compressibletherebetween by said shock absorber connecting member being displacedtoward said stationary shock absorber connector by upward movement ofsaid pivotal wheel support arm to absorb vertical displacement loadstransmitted to said pivotal wheel support arm by the wheel connectedthereto.
 12. A trailer as claimed in claim 11 wherein there is furtherprovided lateral displacement stabilizing and external shock absorbingmeans secured to said pivotal wheel support arm to arrest said pivotalwheel support arm against lateral loads.
 13. A trailer as claimed inclaim 12 wherein said stabilizing and lateral shock absorbing means isconstituted by a vertical extension plate secured to said pivotal wheelsupport arm and having a vertical flat friction surface displaceableagainst a flat vertical arresting surface of said frame, and a bushingof shock absorbing material immovably retained in said frame attachmentmember about said pivot pin.
 14. A trailer as claimed in claim 13wherein said vertical flat friction surface is constituted by anultra-high molecular weight polyurethane plate secured to said surfaceof said vertical extension plate, said vertical extension plate being asteel plate.
 15. A trailer as claimed in claim 11 wherein said shockabsorber connecting member is a flat seating plate secured to a supportframe of said shock absorber connecting bracket, and a connectingfastener securing an end of said shock absorber thereto, said shockabsorber being a pad of compressible material.
 16. A trailer as claimedin claim 15 wherein said stationary shock absorber connector is a flattransverse wall surface formed integral with said frame.
 17. A traileras claimed in claim 11 wherein each of said horizontal side beams arestraight hollow side beams, each said side beam having one or morerectangular wells formed therein from an outboard vertical side wall ofsaid side beam, said well having a transverse flat wall section definingsaid stationary shock absorber connector, and a connecting fastenersecuring an end of said shock absorber thereto, said frame attachmentmember being an attachment bracket secured to a flat bottom wall of saidside beam behind and adjacent said transverse vertical side wall, saidpivotal wheel support arm supporting the wheel connected thereto insidesaid rectangular well.
 18. A trailer as claimed in claim 1, wherein saidfront frame section has a towing frame structure for removableattachment to a hitch of the road vehicle.
 19. A trailer as claimed inclaim 1, wherein there is further provided a manual locking deviceadjacent opposed ends of said side beams to lock said side beams withrespect to said front frame section when said side beams are displacedto an outward position and to lock said hinge arms to said side beamswhen said hinge arms are at an open position, and gate locking means ata free end of said hinge arms to lock said hinge arms together when saidhinge arms are at a closed position.